Fall-calving herds require management that is different from spring-calving herds. In spring-calving herds, the majority of lactation occurs when the cow is grazing vegetative grass that is high in nutrients. In this case, the lactational nutrient needs are being met, especially if cows are grazing cool-season spring pastures. Fall calvers are typically challenged because of the nutrient quality of the forage resource when lactation is occurring. In this case, calf growth while with the cow is reduced because lactational nutrient needs are not met. If you supplement fall calvers during lactation, will calf weaning weight increase? It may or may not, depending on the weather and other factors that the increased supplementation may be used for. So you may wrap a lot of money into supplementation and not get a return.
If calves are not stunted, the data would suggest that once they are in a good feed resource situation, they will gain the weight back. The concern you have with heifers that are selected as replacements is that they need to reach puberty and be cycling before the start of the breeding season. Light weaning weights may make it difficult to develop them at a rate that you feel comfortable with to get them to cycle. So should you creep fed the heifers, especially if they are to be kept as potential replacements? Maybe this is a situation that warrants that management practice. If the heifers are not going to be potential replacements and you retain them, then early weaning and getting them started on a complete ration may be the route to go. It seems to me that fall calves and early weaned calves need to be kept for some time after weaning to pay for cow costs because the calves are light at weaning and won't generate enough total dollars when sold at weaning.
Depending on your situation, fall-born calves are typically at an ideal weight in the spring that they work nicely on spring/summer pasture.
